Method for preparing resistant starch of corn

The invention relates to a preparation method of corn resistant starch, which uses common corn starch as raw material to produce corn resistant starch with multiple physiological functions and characteristics by combined treatment of microbial fermentation and hot pressing and cooling. The resistant starch has physiologic functions of effectively controlling body weight, preventing constipation, appendicitis, hemorrhoids and colon cancer, controlling diabetes, increasing lipid discharge, improving lipid composition, promoting absorption of zinc, calcium and magnesium ions, increasing removal of cholesterol and cholic acid, and reducing cholesterol biosynthesis, lipid absorption and fatty acid biosynthesis. The resistant starch used in food processing industry has better physicochemical properties than those of dietary fiber, low water retention capacity, good mouthfeel, no influence on food, and improve food texture. The invention solves the problems in production of resistant starch, including low yield and lack of high amylase starch in China.